DE102007009543A1 - Microscope device with position detection - Google Patents

Abstract

The present invention relates to a microscope device (15) with a stand (1) carrying a microscope (5) and to at least one detector (21, 22, 23, 24, 26) for determining the spatial position of the microscope, wherein the microscope (5 ) at least one acceleration sensor (24) is present. This allows a drastic reduction of the necessary sensors. Moreover, a reliable position detection can be done regardless of contamination.

Description

The The present invention relates to a microscope apparatus having a a microscope-carrying tripod and at least one detector for determining the spatial position of the microscope.

at many microscopic applications, especially in microsurgery, it is important to know the coordinates of the microscope. In the Microsurgery often becomes image data which over various imaging procedures, such as computer tomography, be obtained, for example in the form of a sectional image in the projected by the surgeon image of the examined object area, to facilitate the examination or surgery. It is of paramount importance that the microscope, the examined object area of the patient as well as any existing ones Third party information (such as the above image data) in real spatial Correlation brought to each other.

A generic microscope device is from the DE 41 34 481 C2 in which a surgical microscope for computer-assisted stereotactic microsurgery of a patient is proposed, which comprises a multi-jointed stand for spatial positioning and alignment of the surgical microscope and a plurality of detectors for detecting the current spatial position and orientation of the microscope. By means of a computer image data are correlated there with the image of a considered object area. So that the sectional image associated with the object area under consideration is superimposed on preoperatively acquired image data, the surgical microscope proposed there has a measuring system which records the distance between the surgical microscope and the object area being considered. This requires the knowledge of the exact space coordinates and the orientation of the surgical microscope. Suitable displacement and angle detectors in the multi-joint tripod are used for precise detection of position and orientation of the surgical microscope.

That in the DE 41 34 481 C2 proposed measuring system further detects the distance of the observed object detail of the respective focal plane and then it determines from the optical system data of the surgical microscope, the relative position of the object detail in front of the surgical microscope. Its spatial coordinates can be detected by means of the mentioned path and angle detectors in the multi-joint tripod. With regard to these detectors, the cited document refers to the DE 40 32 207 A1 ,

In this writing, DE 40 32 207 A1 , The mentioned detectors are constructed of rotary encoders, which are arranged in the respective pivot joints of the multi-joint tripod. Furthermore, a detector for detecting the displacement distance along the optical axis of the microscope is present. A computer unit calculates, on the basis of the detector signals, the displacement distance and the position of the microscope as well as the position coordinates of an observed point within the examined object relative to a reference point within the object. The two-armed tripod used there, which carries the microscope, there are a total of six detectors necessary.

at the proposed angle detectors are usually around raster discs scanned by a suitable light source be detected in order to detect a shift angle, or with motor-driven tripods to angle encoder, the similar can be constructed or due to known engine characteristics allow a conclusion on the displacement angle.

at Motor-driven tripods has the disadvantage that these are not easily displaced manually, as they are have self-locking gear or joints. Become such tripods nevertheless manually operated, can not be assumed be that the angle detection provides reliable data. The aforementioned angle detectors are also susceptible to contamination and work with optics that are inherently flawed. and susceptible to wear. After all also sets the number of detectors needed Significant disadvantage. Not least, such solutions technically complex and costly.

Furthermore is a position detection of the microscope known in which this Position on the location of markers done. Here you can the markers are either attached to the microscope itself and from a fixed location system or the markers can be found elsewhere in the room, for example in the object area, be attached and from a tracking system on the microscope itself be targeted. The use of such markers has the disadvantage that these are caused by other devices, persons or sterile tissues o. Ä. Can be obscured. Also a pollution such markers is a problem.

A (surgical) microscope, in which the observer (surgeon) does not have to look through the eyepieces of the microscope, but has a substantially clear view of the surgical field, which is simultaneously displayed enlarged with respect to the considered detail, is from the DE 10 2004 022 330 B3 known (so-called free-view microscope).

Object of the present invention is in egg nem generic microscope device to make the determination of the spatial position of the microscope easier than before.

These The object is achieved by a microscope device solved according to claim 1. advantageous Embodiments emerge from the subclaims and the following description.

According to the invention suggested that using the microscope as a detector to determine the Position of the microscope at least one acceleration sensor, in particular exactly one acceleration sensor is available. Because of the engagement of acceleration sensors does not become mechanical or optical Contact of the detector to determine the spatial position of the microscope to a reference point (screen or initial position an adjustment motor) is required. The known acceleration sensors work wear-free and are also in extreme situations like in damp or dusty areas, but especially in can be used in microsurgery.

in the Unlike other known detectors for determining the spatial Position of a microscope have the proposed acceleration sensors a small size, low power consumption and finally low production costs. Furthermore is not to determine the spatial position of the microscope a larger number of detectors necessary each turning and shifting point of a multi-unit tripod monitor for a movement and capture that movement, but theoretically it is already a single accelerometer sufficient, which is present on the microscope. Under the feature "am Microscope present "means that at least one accelerometer directly on the microscope or in the microscope housing or on any other point that is rigidly connected to the microscope stands (ie his during a movement of the microscope Position relative to the microscope maintains), is attached.

By The recording of the movement of the microscope can also be its momentary Position reliably determined. In terms of In a direction of movement, this determination is made via a known dual integration of acceleration over time.

Two typical representatives of acceleration sensors are in the following briefly outlined. These are piezoresistive and capacitive Acceleration sensors.

piezoresistive Acceleration sensors are based on the principle of measuring the Deflection of a mass from its rest position due to an occurring Acceleration. For this purpose, an inert mass (silicon) suspended by means of a thin bending beam. As the sensor accelerates, the mass deflects the beam their inertia from its rest position. On the beam applied piezoresistors change due to the resulting mechanical stresses their electrical resistance. Because of this relationship, there are deflections in all measure three spatial directions by means of electrical signals. In terms of Further details may be found in the known literature on piezoresistive Referenced acceleration sensors.

capacitive Acceleration sensors are based on the measuring principle that in a simple plate capacitor with a given cross-sectional area the capacity varies with the distance changed the electrode plates. The corresponding acceleration sensor now has a total of three parallel to each other electrode plates on, with the outer electrode plates fixed are mounted while the middle electrode plate elastic is stored so that this middle electrode plate shifts, if an acceleration force acts on them. Correspondingly change the capacities generated by the three capacitors. From the voltage changes can be on close the acceleration. Because also this sensor type is known per se, for further details on referred to the known literature.

through the proposed acceleration sensors is an acceleration detectable in all three spatial directions (ie measurable, detectable, evaluable and determinable). It also works the orientation, ie a rotation of the microscope around each of the capture three spatial axes. While for some applications only the knowledge of the three spatial coordinates is sufficient, is also common for microsurgery applications the knowledge of the angular coordinates of the microscope desired, by turning the microscope around each one of the spatial axes to be changed. Under "Position of the microscope" should in the context of this application, therefore, the three spatial coordinates and in addition the three associated angle coordinates with respect to To be understood rotations about the three spatial axes. Thus, you can in the optimal case, all six degrees of freedom by the acceleration sensor according to the invention be recorded.

It may be additionally advantageous, if not only on the microscope, but also on the tripod one or more additional acceleration sensors available are. As a result, comparative measurements, plausibility considerations and method for error minimization possible.

The microscope device according to the invention is Particularly suitable for microscopes that are mounted freehand movable on the tripod.

The Microscope device should have a control unit for recording and Processing of those data, by the one or more acceleration sensors be recorded or delivered.

Farther If an evaluation unit for display (ie playback, display, Determination or output) of the spatial position of the microscope be provided. Such an evaluation unit is in particular the downstream control unit and calculated from the in The control unit processed data spatial coordinates and angular positions of the considered microscope. This evaluation unit can are a known navigation system.

It is necessary, the position of the microscope with respect to a reference point be given, advantageously for this purpose a solid Room point is selected. When using a ceiling mount is expediently this fixed point in space in the suspension area of the ceiling stand, ie in the suspended column of the tripod or in the transition from column to ceiling. Other suitable and known solid spatial points are also used as a reference point (Zero point of the coordinate system) possible. This should be if possible, the reference point also after finished Examination (operation) or after moving the object (patient) or the object table (patient table) do not change.

at Using a floor stand makes sense to do this before starting to put the investigation or operation in a fixed position, which did not change during the examination or surgery becomes. It is useful in this case, the fixed point in space into the area of the object to be examined. So will be about in operations on the head of a patient, the patient's head with a fixed special stereotaxier frame, in turn, with the operating table can be firmly connected. A reference point on this stereotaxier frame can therefore be used as a reference point (zero point of the coordinate system) serve.

at Use of a floor stand changes after the examination or operation usually the location of the reference point, as both the examined object (patient) as well as the ground stand in the Usually be changed in their position. Thus, after switching off of the microscope / moving the microscope stand or after moving the microscope Examination / operating table a renewed calibration done.

The The invention and its advantages will be described below with reference to an embodiment, which is illustrated in the attached drawing, closer be explained.

It shows

1 a microscope device according to the invention in a schematic side view.

1 shows the schematic side view of a microscope device 15 with a surgical microscope 5 that of a tripod 1 worn. The surgical microscope 5 is movable in all three spatial directions (translational and rotational). In the embodiment according to 1 it is a floor stand 1 that on a floor 10 stands. The tripod 1 has advantageous magnetic brakes, the activation of the set position is fixed. When deactivated, the respective joints are freely movable. The illustrated tripod 1 has freely movable joints, as there are no self-locking gearboxes. The tripod 1 points next to the perpendicular to the floor 10 standing tripod column 12 a scissor arm 2 on, which in turn consists of two interconnected via a hinge arm parts. The scissor arm 2 is about another pivot with the tripod column 12 connected. On his other side is the scissor arm 2 via another rotary joint with a support arm 7 connected to the microscope 5 is appropriate. Between support arm 7 and scissor arm 2 can be an XY adjustment 3 by means of which the support arm 7 and the microscope on it 5 in a plane perpendicular to the plane of the drawing is additionally movable by motor (especially after activation of the magnetic brakes).

The on the support arm 7 attached microscope 5 includes - as is known - a main objective 6 and a tube 4 with eyepiece, these known components are shown only very schematically. The microscope 5 is translationally displaceable in all three spatial directions. Moreover, it is so on the support arm 7 attached so that it is rotatory about all three spatial directions.

With 9 is the schematically illustrated observer eye, for example, the eye of a surgeon, through the eyepiece of the microscope 5 looks. The microscope 5 forms an area on the object 11 (Patient) increases. With 25 is a reference point or generally measuring point on this object 11 designated.

A data mirroring unit 8th is in front of the tube with eyepiece 4 in the microscope 5 connected. By means of such a data input unit 8th For example, image data (such as computed tomography tomograms), but also numerical data, crosshairs, and the like, can be included in the microscope image and correlated to the respective microscope image be reflected. For example, a CT diagnostic section image can be simulated to the respective location of the operation reproduced by the microscope image and thus superimposed on the microscope image in order to better match diagnosis and operation. Other data reflections (numerical information, for example of size ranges, crosshairs, arrows, etc.) are thereby possible.

In principle, a single, with the reference numeral 24 sufficient acceleration sensor to each position of the microscope 5 capture. These include, as already stated, changes with respect to all six possible degrees of freedom (three translational and three rotational degrees of freedom). For reasons of redundancy (confirmation of the result, error minimization, plausibility consideration), further acceleration sensors may be present. These are exemplified by the sensors 21 . 22 and 23 shown, which are attached to the tripod column 12 as well as on the two arms of the scissor arm 2 are located. In addition, an acceleration sensor 26 at the XY adjustment device 3 be provided.

The data of the sensor 24 (and any other sensors 21 . 22 . 23 and 26 ) become a control unit 20 fed and processed there. The processed data becomes an evaluation unit 30 fed, which is designed here as a navigation system. This navigation system 30 can be a screen or an external computer unit 40 be followed by the optical display or further data processing. On this screen 40 For example, the coordinate system and the position of the microscope 5 or the acceleration sensor 24 with respect to the object 11 be visually displayed. Furthermore, it is possible on this screen 40 to present the same view as the observer or inspector 9 sees, in particular so the microscope image with any Dateneinspiegelung. Screen and / or external computer unit 40 are particularly suitable for remote monitoring or remote viewing of the examination or operation process.

The evaluation unit controls the data input 30 a data input unit 8th in the microscope 5 at. Depending on the examined object area, previously stored data (for example, sectional images or numerical data) can be selected to match the microscope image and superimposed thereon. The data input is known per se, so that reference can be made to known literature.

In this embodiment, for example, takes place before an operation of a patient 11 a calibration or calibration of the floor 10 fixed tripod 1 , As a reference point 25 For example, a particular point on the stereotactic frame is used to fix a patient's head during surgery. This point 25 then represents, for example, the zero point of the coordinate system, so that all movements of the microscope 5 in relation to this reference point 25 recorded and calculated. After switching off the system (moving the tripod 1 ) or after moving the reference point 25 (Moving the operating table or the stereotactic frame), a new calibration or calibration must be performed. Thanks to the downstream navigation system 30 It is also possible to reliably retrieve certain detected positions within an operating cycle. Furthermore, the image data of sectional images already mentioned in the introduction to the description can be faded into the associated object images with high accuracy.

By using acceleration sensors in the microscope device according to the invention 15 the coordinate detection of the microscope is formed 5 extremely robust, regardless of any contamination of the microscope 5 or the acceleration sensor 24 and little prone to errors, since the accelerometer 24 purely electronic works. Furthermore, the sensors operate at low power consumption and are available at low cost. Of course, the invention can also be used advantageously in the case of the above-mentioned free-view microscopes.

1

tripod

2

Scherenarm

3

XY-adjusting

4

tube with eyepiece

5

microscope

6

main objective

7

Beam

8th

Dateneinspiegelungseinheit

9

observer's eye

10

floor

11

Object, patient

12

pillar

15

microscope apparatus

20

control unit

21 22, 23, 24

accelerometer

25

Measuring point reference point

26

accelerometer

30

Navigation system, evaluation

40

Screen, external computer unit

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• DE 4134481 C2 [0003, 0004]
• - DE 4032207 A1 [0004, 0005]
• DE 102004022330 B3 [0009]

Claims (12)

Microscope device ( 15 ) with a microscope ( 5 ) carrying tripod ( 1 ) and at least one detector ( 21 . 22 . 23 . 24 . 26 ) for determining the spatial position of the microscope, characterized in that at the microscope ( 5 ) at least one acceleration sensor ( 24 ) is available. Microscope device according to claim 1, characterized in that exactly one acceleration sensor ( 24 ) on the microscope ( 5 ) is available. Microscope device according to claim 1 or 2, characterized in that in addition to the tripod ( 1 ) at least one acceleration sensor ( 21 . 22 . 23 . 26 ) is available. Microscope device according to one of claims 1 to 3, characterized in that the microscope ( 5 ) Freehand movable on tripod ( 1 ) is attached. Microscope device according to one of claims 1 to 4, characterized in that a control unit ( 20 ) for receiving and processing by the at least one acceleration sensor ( 21 . 22 . 23 . 24 . 26 ) is provided. Microscope device according to one of claims 1 to 5, characterized in that an evaluation unit ( 30 ) for determining and / or displaying the spatial position of the microscope ( 5 ) is provided. Microscope device according to claim 6, characterized in that the evaluation unit ( 30 ) determines or displays at least three, preferably six position parameters. Microscope device according to claim 6 or 7, characterized in that the evaluation unit ( 30 ) is configured such that the position of the microscope ( 5 ) is determined or displayed with respect to a fixed point in space. Microscope device according to claim 8, characterized characterized in that when using a ceiling stand, the solid Spatial point is in the suspension area of the ceiling stand. Microscope device according to claim 8, characterized in that when using a floor stand ( 1 ) the fixed point in space ( 25 ) in the area of an object to be examined ( 11 ) lies. Microscope device according to one of claims 6 to 10, characterized in that the evaluation unit ( 30 ) comprises a navigation system. Microscope device according to one of claims 6 to 11, characterized in that the evaluation unit ( 30 ) with a data input unit ( 8th ) on the microscope ( 5 ) for reflecting correlated data into the microscope image.